In the final boss fight, your actions are as follows:
# YELLOW button moves your Vital Suit upwards
# GREEN button moves your Vital Suit downwards
# BLUE button fires pulse lasers
# LEFT TRGR fires lasers or does a large sideways cut if you hold it
# RIGHT TRGR does a saber stab or does a vertical cut if you hold it
The final bosses weaknesses are the large cutting attacks activated by your TRIGGERs. Just get in close to him and keep cutting him unitl he dies and be sure not to get caught in his purple laser attack. Don't bother using the pulse lasers since they don't do anything to the boss except to destroy the missiles fired at Wayne. Personally I think the best cutting attack to use is the sideways cut as you rarely miss him. The vertical cut can miss if the boss moves sideways.
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